This agreement covers breaches between May 28 and June 6 2013, but Slater & Gordon is alleging that Newcrest's wrongdoing occurred much earlier.

"Our clients allege that Newcrest had no reasonable grounds for the gold production guidance it released on August 13 2012," said Slater & Gordon's senior class action lawyer Ben Phi.

"While our clients welcome Newcrest's admissions, we allege that these contraventions form part of a wider course of misconduct."

Newcrest says Slater & Gordon's allegations go far beyond the settlement it reached with ASIC, and will be denied.

"The proceeding raises issues beyond the subject matter of the ASIC settlement referred to in Newcrest's 28 June 2014 announcement. Newcrest intends to vigorously defend the proceedings," the company said in a statement.

Mr Phi says many Newcrest shareholders, large and small, are involved.

"We have been retained by a significant number of retail and institutional shareholders and the losses claimed are substantial," he added.

The claim is being brought on behalf of all persons who acquired Newcrest shares between August 13 2012 and the close of trade on June 6 2013.